                     (cons a (lazy-seq (read-fn* r refs)))))]
     (read-fn rdr (.refs rdr))))
 
-(defn read-blocks-sequentially*
+(defn- read-blocks-sequentially*
   [^BAMReader rdr mode]
   (let [read-block-fn (case mode
                         :normal read-alignment-block

                    (cons b (lazy-seq (read-fn* r refs)))))]
    (read-fn rdr (.refs rdr))))

(defn read-blocks*
  [^BAMReader rdr
   ^String chr ^Long start ^Long end]
  (when (nil? @(.index-delay rdr))

      (read-alignments-first-only rdr spans window read-fn)
      (filter window candidates))))

(defn- read-alignments-sequentially*
  [^BAMReader rdr deep-or-shallow]
  (let [read-aln-fn (case deep-or-shallow
                      :shallow light-read-alignment
